CANCER–The word alone is enough to scare most people. It conjures up scary visions of suffering and mysterious treatments.

Dan was frightened. He wasn’t ready to admit it to anyone yet, but he was really scared. His doctors had told him that he had cancer. They wanted him to start chemotherapy in a few weeks. Today he felt pretty good–a little tired but well, in general. He looked around the waiting room at the doctors’ office. Some of the other patients looked a lot sicker than he did. He could tell that one person with a scarf on her head had lost all her hair. That kid in the corner had no hair, either. His dad gave him a reassuring little punch.

Dan kept overhearing things that sounded terrible. “I was so weak after that last chemo.” Why take medicine to make you feel worse?

And that older woman was wearing a surgical mask. Did she have some strange disease, or was that because of chemotherapy, too? Dan wasn’t too sure he wanted to find out more. But that was why he was here: so the doctors could explain what was happening.

What is Cancer?

Today, the outcome after a diagnosis of cancer is more positive than ever before. Many types of cancer are treatable and seem to be curable. One way to treat and often seemingly to cure cancer is through chemotherapy.

Before we talk about the treatment, let’s make sure we’re all talking about the same thing when we use the word cancer.

Most of the cells in your body grow, then divide, to create new cells. How fast this process happens depends on the type of cell you look at. Bone cells change fairly slowly after people have reached their final height. Cells divide to replace old cells or to repair damage. Blood cells have a different life story. Blood cells divide frequently.

Normally, red blood cells stay in the blood for about three or four months. Then they are replaced with new cells. There are also white cells in your blood. Among other things, these cells help your body fight off infections. Some white cells last only a week or two. Others don’t even survive for a full day. These cells also are replaced by cell division

There is a specific timetable for cell division, growth, and development of each type of cell in your body. But sometimes the control system for the division and development of cells doesn’t work as it should. That’s what we call cancer. The word cancer usually means that one cell or group of cells begins to divide uncontrollably. Usually, the cells that are produced do not develop into specialized cells. They stay immature and keep dividing.

If the cells that are out of control are one type of blood cell, then that part of the blood no longer does its job. Other blood cells may not be produced. If the cells that are out of control are part of another tissue–bone or liver, for instance–then they may interfere with that tissue’s function. In addition, a mass of cancer cells, or tumor, may form. This can put pressure on the rest of the organ or on other organs and interfere with normal functions.

Usually, the doctors have three choices for cancer treatment: surgery, radiation, or chemotherapy. Often, two or three of the choices are combined. What kind of cancer, where it is, and how far it has progressed all are part of the information doctors use in deciding on treatment.

Is the Treatment Worse Than the Disease?

Chemotherapy is literally treating cancer with chemicals: drugs. But this is different from most kinds of drug therapy. When you have an infection, for example, the doctor prescribes an antibiotic, a drug that will kill the bacteria causing the infection. Bacteria are different from body cells; drugs that kill them most often have no effect on your own cells.

Cancer, however, really is your own cells that have gone out of control. Drugs that will kill cancer cells also will have an effect on the rest of your cells. Doctors try to work with what makes cancer cells different, to find ways to kill the cancer cells with little harm to the rest of the body. They often are not completely successful. What you see or feel are side effects of the chemotherapy.

Cancer cells usually are very simple and divide continually. Many drugs used for chemo are drugs that interfere with cell division. But cancer cells aren’t the only cells in your body that are dividing.

Cells deep inside hair follicles divide rapidly, causing your hair to grow. Many drugs used for chemotherapy also damage the cells in hair follicles. When that happens, hair falls out. People on chemo can lose all their hair, sometimes including their eyebrows and eyelashes. But once the drug therapy stops, the cells continue to divide and new hair grows in.

Another group of cells that divide and may be damaged by chemotherapy are the cells that line the digestive tract–that is, the stomach and intestine. Those cells normally let the nutrients from the food you eat get into your blood. If the cells are damaged, a person may feel sick. Vomiting and diarrhea can occur after chemotherapy. The people getting treatment may not feel like eating; they may lose weight. But again, when the chemotherapy is over, these cells will be replaced. Appetite returns.

Other cells that can be affected by chemotherapy include blood cells. Your blood contains several different kinds of cells. Red cells are replaced every three to four months. If chemo slows down their production, old cells aren’t replaced fast enough. People getting treatment may become anemic; that is, they do not have enough red blood cells. These cells help carry oxygen to all your cells. If you don’t have enough, then your cells won’t get enough oxygen. You feel weak and tired. You may not be able to do normal things, like run for the bus or rush up the stairs, without getting breathless and tired.

Other cells in the blood, the white blood cells, help the body fight infection. Some of these cells are normally replaced every few days. If chemo interferes with replacing white cells, the result can be that the body is less able to fight off infection. People on chemo have to be very careful. They may be told to stay away from crowds or to wear a mask to reduce the number of bacteria they breathe in.

Controlling the Side Effects

These effects are reversible. As soon as chemo ends, the normal cells should replace themselves. Hair will grow back; normal immunity should return; energy levels should be close to what they were.

Doctors don’t want to scare away people like Dan. They really don’t want to make their patients sicker than they felt before. For some types of cancer, chemotherapy is very effective and can cause the cancer to disappear.

But the side effects have been hard to tolerate. New drugs have changed the picture a little. In some kinds of cancer, doctors can use two or three drugs in smaller doses. The combination has the same effect on the cancer as a higher dose of one drug, but the side effects may be significantly lessened.

Also, some of the side effects, such as nausea, vomiting, and diarrhea, now can be controlled in some patients by giving other drugs with the chemotherapy. Some of the newer chemotherapy drugs have fewer, milder side effects.

Chemo and the Future

Cancer treatment continues to evolve. The patient’s overall health is also important as new treatments help control or cure the cancer with fewer or less-serious side effects.

Dan still has worries and fears. But knowing what to expect from his treatment and knowing that the newest, safest drugs are being used help reassure him. He may have problems with side effects, but those problems will end. He can put up with them to conquer this cancer, once and for all.